Gladiator of the Deep

          For speed, range, power and endurance, he swordfish stands alone among marine predators.

BBBBBBy Tom Fort

The broadbill swordfish, Xiphias gladius, stands alone among the great marine predators. It has relatives but no close family. Its range is enormous, its ability to function at different depths—anywhere between the surface and 4,000 feet down—extraordinary. Its colossal blue eyes, warmed by heat-producing tissue in the head, enable it to feed in the deep darkness and respond to the phases of the moon. It can grow to 1,500 pounds and more and attain a length of 15 feet, a third of it made up of its mighty sword, or bill. No other fish, not even a marlin, can quite match it for the combination of size, speed, power and endurance. "If ever a fish deserved a book of its own, it is this one," Richard Ellis reflects, and in his fine, wise and endlessly illuminating "Swordfish: A Biography of the Ocean Gladiator" he has produced one worthy of it.

Mr. Ellis wears his learning lightly and manages the difficult trick of covering a great deal of factual ground thoroughly but without becoming tedious. Sensibly he tells much of the story through the words of others—commercial fishermen, anglers, scientists, environmental campaigners—who have studied, hunted or merely marveled at the wondrous swordfish. But he is no slouch with a phrase himself. "The adult swordfish is a graceful, tapered teardrop of a fish," he writes. Of the dorsal fin he observes: "It remains permanently erected, announcing its presence like a heraldic gonfalon."

The authorial voice is firm without being didactic or strident. Occasionally Mr. Ellis becomes impatient. He characterizes one of the swordfish's early chroniclers, Frank Bullen, as "sometime whaleman and full-time fantasist," scorning Bullen's claim to have seen a swordfish burying its sword in a porpoise as "ridiculous nonsense" (though it's worth noting that there are entirely reliable accounts of swordfish attacking boats, submarines, oil pipelines and people). A favorite book of my boyhood, "Battles With Giant Fish" (1923), by the English adventurer and charlatan F.A. Mitchell-Hedges, is mercilessly—but I'm afraid fairly—mocked for its exaggerations and absurdities.

Allusions to the literature of the sea spice Mr. Ellis's text. Some were familiar to me, some not, but all help build a picture for those—such as myself—who have never seen the swordfish in its element. I fear now that I never will, living as I do a long way from the ocean paths followed by this epic wanderer. But I can see it in my mind's eye in all its fierce, muscled glory. I had my first, astonishingly vivid encounter with it many years ago, through the writing of its most eloquent admirer, Zane Grey.

Of Grey, Mr. Ellis judges acutely that—in contrast to Ernest Hemingway, a writer who fished—he was a fisherman who wrote, "and wrote superbly." Grey was as obsessive in his pursuit of swordfish as with everything else in his deeply obsessive life. This, after all, was a man who once spent 83 consecutive days fishing without catching a single fish ("that is a record that will stand," he wrote with grim satisfaction).

Grey called the swordfish "the noblest warrior of all the sea fishes," and he gloried in the bloody business of matching his strength against its survival instinct. Yet he knew almost nothing about its biology, taxonomy, migrations, diet or habits. Both he and Hemingway—whose principal angling mania was marlin—invariably referred to their quarry as "he," even though all the biggest swordfish and marlin are female. In Mr. Ellis's words, the authors "were probably psychologically incapable of conceding such dominant power and size to a female." Had they known the truth, they might have needed therapy or, more likely, would have switched to killing something indubitably masculine.

Mr. Ellis is a good-humored guide. One of his photographs shows a plate of grilled swordfish, mashed potatoes and zucchini with—according to his caption —"maybe a soupçon of mercury." In general, he even manages to keep his temper when recounting the catastrophic collapse in swordfish stocks brought about since the early 1980s by industrial fishing with drift nets and, later, long lines, although every now and then burning outrage bursts through. For instance, Mr. Ellis quotes a passage by the ecologist and campaigner Carl Safina detailing the slaughter along the eastern seaboard of the U.S. Between 1989 and 1996 catches by American boats fell by 60% even as the number of hooks set by long-liners doubled to more than 11 million.

"These numbers are beyond incomprehensible," Mr. Ellis writes. "They demonstrate an appalling ignorance on the part of consumers—should every fish in the ocean be killed so people can eat swordfish steaks?—and the almost pathological unwillingness of swordfishermen to recognize that they are killing the goose that lays the golden egg."

And the slaughter goes on. Despite international regulations on size limits, Mr. Ellis relates, Italian tuna fishermen supplement their earnings by selling baby swordfish as small as two feet long at the roadside—"an incredible massacre . . . an abominable procedure," he thunders. It is amazing, given the greed and reckless blindness of human beings—whether fishermen, consumers, restaurant chefs or so-called regulators—that the swordfish has escaped complete annihilation; it is heartening to know that in some of its feeding grounds it is even staging a tentative recovery.

Mr. Ellis has trawled a vast range of sources to present the current state of swordfish knowledge in a clear, accessible and—to this pisciphile reviewer—riveting way. He also has the humility to concede the limits of that knowledge. Even now, for example, we are not sure how the swordfish uses its mighty bill. We assume that it is for incapacitating its prey by slashing at it, but the details remain conjectural. Similarly it is known that swordfish travel huge distances, but—as Mr. Ellis says—"nobody really understands their migration." And why not? Because swordfish are loners. Unlike tuna, they do not school together, which makes them hard to track. In other words, they hold on to their secrets.

Speaking for myself—and, I suspect, for Mr. Ellis, as well—I am delighted that they do. It is good to know more than we did, and I would be surprised if there is a single pertinent fact about swordfish that is missing from Mr. Ellis's commendably concise text. But it is the mystery of fish and fish lives that makes them so beguiling. We can intrude on their world, for sport, sustenance or study. But we do not belong in it, so we can never know it all, which is just as it should be.

—Mr. Fort's books include "The Book
of Eels" and "The Far From
Compleat Angler."

A version of this article appeared June 15, 2013, on page C7 in the U.S. edition of The Wall Street Journal, with the headline: Gladiator of the Deep.